Manufacture of bodies for tools and the like from materials such as carbides, the alloys thereof, and the like



Patented May 6, 1930 UNITED STATES PATENT OFFICE mar, 'sorrnorEn, F BERLIN-LICHTENBERG, AND Hens WOLF or BEELIE, .QEE-

MANY, 'ASSIGNORS T0 FRIED. KRUPP AKTIENGEsE nsC A T, or vEsanti anina,

GERMANY MANUFACTURE or BODIES FOR roots AND THE LIKE FROM Arnnmrs seen ts BIDES, THE ALLOYS THEREOF, AND HE LIKE No Drawing. Application filed June 10, 1929, Serial No. 369,913, and in Germany June 15, 18 28.

Our invention relates to improvements in the manufacture of bodies for tools and the like from materials such as carbides, the alloys thereof, and the like the working of first pressing the materials nearly into the desired form, thereafter subjecting the same topreliminary sintering at low temperature for transforming'the same into a state allowing working by means of tools, imparting the final shape thereto by cutting tools, and

-- finally subjecting the blank to high sintering.

In carrying out this method it is necessary during the preliminary sintering operation to heat the blank exactly at the proper temperature, because when the temperature is not sufficient the body is brittle, and when the temperature is too high the hardness of the blank is such that economical working v by means of cutting tools is not possible.

The object of the improvements is to prov vide a method by means of which bodies of any desired shape can be easily manufactured, and with this object in View our, invention consists in forming a hard and rigid body of the desired form from the said powdered material and a suitable binding medium hardening at ordinary temperature or at slightly elevated temperature, thereafter imparting exactly the desired form to the said body by mechanical working, and

finally sintering the same at high sintering temperature. The raw material consists of carbides of metals having a high melting point or of mixtures of such carbides with metals having a lower melting point, such for example as iron, cobalt or nickel, and the binding medium may be added to the said material either before or after pressing the same into the desired shape. By adding the said binding medium to the raw material a 50 body is produced which is sufliciently coherent to permit worln'ngbymeans. of vsuitable tools in the same way .as the bodies heretofore made by the reliminary sintering process. For examp tothe hard and rigid body produced by means of thebindmg medium the desired form, for exainple sharp cutting edges, can be imparted by ing media, resins, lacquer, patties, such as gum arabic, dextrin, shellac, -z ellIon, colophony. Good results have been obtainedby .addmg a to alcoholic solution of shellac to the powdered'raw material of high melting point, or by. adding the, said solution to the body pressed fromthesaid raw material. However, we wish. it. to be understood that we do not limit ourselves toa binding medium in solution or in suspension-in a suitable liquid, and' that .we may also .use a cementing or gluing medium such as shellac orcolophony, which is softened at. low tem perature, or metals or metalloids oflow melting point, which matter is added to the powdered raw material of high melting point.

-When using. such materials the body is heated,

during or after pressing, at a comparatively low temperature which is not sufficient to cause preliminary sintering, for temporarily transforming the said solid binding medium into a state permitting gluing or cementing of the powderedpraw material. .The solid bodyjof raw material produced by solidification of the binding medium canjbe subjected to mechanical working, in the samewayas a hard body subjected-topreliminary sintering, and more particularly it can be worked filing, the high sintering process ollowing the mechanical working of the pressed bodies the binding medium is removed, or

slight residues remain in, the body which do L not impair the quality of the final object.

The material. removed from the. blank by v .90 by turning, boring, fraismg, sawm and can be used in the same way as the fresh raw material.

We claim:

1. The herein described method of manufacturing bodies from material such as car- (7 bides, alloys thereof, and the like, which con sists in producing a body composed of the powdered raw material and a binding me- .dium adapted to bind the powdered raw material into a hard and coherent body, allowing the said body to harden, impartin thereto the desired shape by mechanical working, and thereafter subjecting the same to high sintering temperature.

2. The herein described method of mama facturing bodies from material such as carbides, alloys thereof, and thelike, which consists in mixing'the powdered raw material with a binding medium adapted to transform the same into a hard coherent body, pressing the material and binding medium nearly into the desired form, allowing the same to harden, imparting the final shape to the blank, and heating the same at sintering temperature.

diumadapted, to bind the powdered raw material into a hard and coherent body, allowin the said body to harden, and thereafter su jecting the same to high sintering tem- 3. The herein described method of manu- 4 facturing bodies from material such as car- ,bides, alloys thereof, and the like, which, consists in pressing the powdered raw ma-' terial-nearly into the desired shape, adding thereto a binding medium adapted to harden with the raw material into a coherent hard body, allowing the raw material and binding medium to harden, im arting the final shape to the blank by mechanical working, and heating the same at sintering temperature.

4;. The herein described method of manufacturing bodies from material such as carbides, alloys thereof, and the like, which consists in producing a body composed of the powdered raw material and a binding medium in a suitable liquid adapted to bind the powdered raw material into a hard and coherent body, allowing the said body to hard en, imparting thereto the desired shape by mechanical working, and thereafter subjecting the same to high sintering temperature.

5. The herein described method of manufacturing bodies from material such as carbides, alloys thereof, and the like, which consists in producing a pressed body nearly of the desired final form from the powdered raw material and a powdered solid binding medium adapted to be made soft by heating and to bind the raw material into a hard and coherent body, softening the binding medium and allowin the same to harden again, imparting the final shape to the blank by mechanical working, and heating the same at sintering temperature.

6. The herein described method of manufacturing bodies from material such as carbides, alloys thereof, and the like, which consists in producinga body composed of'the powdered raw material and a binding me- 

